Printing press machinery



Feb. 6, 1962 L. WENCZLER 3,019,728

PRINTING PRESS MACHINERY Filed March 25, 1960 2 Sheets-Sheet 1 Feb. 6, 1962 WENCZLER 3,019,728

PRINTING PRESS MACHINERY Filed March 25, 1960 2 Sheets-Sheet 2 I74 usuro E AamJ/G- wsrlcz LEQ 13 kmmvef dtates ire This invention relates to apparatus and devices for the clamping of printing plates, such as stereotype plate and the like, onto the plate cylinders of rotary printing presses and, more particularly, to apparatus for such clamping by means of movable clamping hooks mounted in the plate cylinder for engaging recesses on the under side of the printing plates and operated, separately for each plate across the plate cylinder, by a shaft and gearing arrange ment accessible at the end of the plate cylinder.

As is well known, in the mounting or clamping of printing plates, such as stereotype plates and the like, onto the surface of the printing cylinders of rotary printing presses, it may be desired to have such plates held firmly onto the cylinder by clamping means wholly beneath or covered by the plates so that the outer printing surface of the plated cylinder is not interrupted by clamping devices, particularly in web-fed continuous printing presses, and also so that the plates are held firmly onto the plate cylinders against the inevitable play of centrifugal forces present with high speed printing and despite some flexing or stretching which may be inherent in the particular material from which the plates are made.

If it is attempted to accomplish the foregoing by an arrangement of movable hooks rotatably or pivotally mounted within 'the plate cylinder on a shaft extending across the entire cylinder, some difficulties may be experienced in obtaining a firm and uniform clamping pressure of the hooks clear across the cylinder due to torsional effects on the shaft on which the hooks are pivotally mounted, and particularly in Wider presses. Similarly, particularly with high speed presses of substantial Width, the considerable weight of type-metal stereotype plates may, indeed, accentuate such non-uniformity of clamping under high centrifugal forces to which such plates are subjected in use, with substantial damage, or at least down time, resulting from such loosening, and, particularly in situations Where a number of different (and, hence, dimensionally varying) separate printing plates are to be mounted across or around a plate cylinder on the press.

Similarly, if it is attempted to compensate for the foregoing situations by individually mounting the several clamping means pivotally within the cylinder for operation into clamping position by a separate camrning action from the end of the cylinder, difliculty may be experienced, particularly with plate cylinders along which a plurality of adjacent printing plates are to be positioned, in the situation where only the clamping means for one of several plates is desired to be operated without also opening or closing the clamping means for other adjacent plates. Thus an advantageous clamping arrangement is disclosed in the copending application of Paul Dietrich, Serial No. 775,487, filed November 21, 1958, but without provision for separately operating a plurality of coaxially arranged clamping devices as may be desired with a plate cylinder along which a plurality of printing plates are to be positioned in substantially exact axial alignment. According to this invention, however, a firm and uniform clamping of a plurality of printing plates, such as stereotype plates and the like, across the plate cylinder of a rotary printing press is achieved by providing, mounted in the plate cylinder, a plurality of swingable hooks for engaging arecess on the under side of each printing plate atent to be mounted along the cylinder, with the hooks for engaging each separate plate being forced into clamping position by the cam action of a rotating member or shaft, and with the clamping hooks for each plate along the plate cylinder being operated by a separate camming member or shaft extending along the cylinder for the longitudinal extent of each separate plate. As a further feature of this invention, all said separate rotating camrning members or shafts are operable for moving each of said'plurality of books for each of said printing plates into clamping position by an operating means accessible at one end or the other ofthe plate cylinder, and notwithstanding the fact that each of said carnming members or shafts extends longitudinally of said cylinder substantially only to the axial extent of its respective printing plate on said cylinder, the operation of those of said shafts or camming members effective upon clamping hooks for printing plates axially spaced along said cylinder from either end thereof being effected through a jack-shaft and gear train. arrangement operationally accessible from one end of said cylinder as readily as the camrning mechanism or shaft for aplate adjacent said end of said cylinder is accessible to the operator of the printing press.

One object of this invention is to provide means for clamping opposite axial edges of printing plates and the like to the plate cylinder of the rotary printing press with the torsion-resisting operation of a camming of a plurality of clamping members (as disclosed in the aforementioned copending application) but with separate control of the carnming or clamping forces of said hooks individually for a plurality of printing plates mounted along said plate cylinder.

Another object of this invention is to provide means of the character described for separately controlling the carnming action for moving a plurality of clamping members into clamping position with regard to a plurality of different printing plates mounted along and around a plate cylinder of a rotary printing press, and for separately operating each of said means from a readily accessible position to an end of said printing cylinder axially beyond the area covered by any or all of said separate printing plates.

A further object of this invention is to provide, in a combination of the character described for application to printing machinery, additional means for adjusting and controlling the axial positioning of the plurality of printing plates on a plate cylinder of the printing press, such axially positioning means being disposed on or in said cylinder so as to be accessible and functioning independently of clamping means in said cylinder for individually clampim the axial edges of a plurality of printing plates thereon.

Other objects and advantages of this invention will be apparent from the following description, the accompanying drawings, and the appended claims.

In the drawings:

FiG. l is a view, partially in axial section of a por tion of a printing press plate cylinder embodying this invention and showing a portion of such a cylinder at one end thereof;

FIG. 2 is a partial transverse section. along the line II II of FIG. 1;

FIG. 3 is a partial plan view on a somewhat larger scale of the right-hand end portion of FIG. 1;

FIG. 4 is a partial transverse section along the line IV-IV of FIG. 3;

FIG. 5 is a partial transverse section along the line V-V of FIG. 1; and

FIG. 6 is a partial detail top plan view of the mechanism shown in FIG. 5.

Referring to the drawings, in which like characters of reference refer to like parts through-out the several views thereof, a portion of a printing press plate cylinder having the invention applied thereto is indicated in FIG. 1, it being understood that only a portion of the cylinder at one end thereof is shown and that a hub, etc., arrangement is provided at the other end of the cylinder in a manner well understood in this art. As illustrated, a plate cylinder 16 is provided, having a conventional end 11 and hub or boss 12, for accommodating a plurality of printing plates or stereotype plates 15, 16, etc., clamped around and along cylinder 10, which plates, for purposes of illustration, are indicated as having an axial dimension L along cylinder 10.

As indicated more particularly in FIG. 2, the plates 15, 16, etc., may have, as is well known, a circumferential extent of somewhat less than half the circumference of cylinder 10, and are secured therearound by a plurality, of clamping hooks or members 201 having barbed radially outer edges 21 for engaging in slots 22 along opposite axial edges of the under side of plates 15, 16, etc. Clamps 20 are mounted in cylinder for pivoted or swinging movement with respect to slots22, such mounting in the illustrated embodimentbeing provided by a generally cylindrical portion '23 on clamps 20 engaged in a generally cylindrical slot24 extending axially within cylinder 10-generally an arrangement of the character disclosed in the above mentioned copending application.

As noted in FIG. 1, there is, preferably, a plurality of clamps 20 for engaging each edge of plates 15, 16, etc., and spaced axially therealong. As indicated-in FIG. 2, those of the clamps 20 which engage one edge of plates 15, 16, etc. (at the right side of FIG. 2), are preferably urged into the clamping or locking position shown by resilient means such as springs 25 to accommodate, for example, any stretching or flexing of the plates which may occur particularly at high speed operation, while still maintaining a firm clamping engagement thereof to the plate cylinder 10. The other clamps 20 which engage the opposite edge of the plate 15, 16, etc. (at the left side of FIG. 2), are positively moved into the clamping position illustrated by rotation of an axially extending cam shaft 30 rotatably mounted as in a cylindrical channel 31 extending axially in cylinder 10.

Cam shaft 30 has an axial flat 32 therealong, and, as will be apparent from the foregoing, rotation of shaft 30 into the position shown in FIG. 2 earns the associated clamps 20 into the clamping position shown with respect to slot 22 in the under side of plate While rotation-of shaft 30 clockwise. in the drawing, to bring fiat 32 adjacent the surface of the clamps 20, permits the clamps to swing out of clamping position about the cylindrical pivot portions 23 thereon. Also, as noted, the use of such camming action of shaft 30, which is preferably spaced radially outwardly of the axis of the pivoting of the clamps at 23, permits a firm and positive uniform clamping or closing force on each of the several clamps 20' spaced along the edge of plate 15 and substantially free of twisting or torsional non-uniformity which might occur ifrit were attempted to apply the entire clamping force through a shaft on which the plurality of clamps 20 were mounted at the pivot axis thereof.

As indicated in FIG. 1, it is desired to have the clamps 2% for each plate 15 or 16 independently operable, and so, as indicated in FIG..1, cam shaft 30 extends axially of cylinder 10, from a point accessible at the end of this cylinder for operation of cam shaft 30 by a mechanism described below, only so far as is required to operate all of the clamps 20 associated with one edge of plate 15. For the operation of those of the clamps 20 associated with one edge of a different plate 16, a separate cam shaft 35 is provided axially within cylinder 10 and extending axially thereof substantially only through the extent of cylinder 10 overlaid by plate 16. As will be understood from the foregoing, cam shaft 35 is positioned coaxially with cam shaft'fit in cylinder 10- andoperates with respect to those of the clamps 2% associated with it in the same manner as indicated in FIG. 2 for cam shaft 3ti'-although the actual mechanism for rotating shaft from the point accessible from the end of the cylinder is somewhat different, as described below, and includes a jack shaft 36 rotatably mounted axially in cylinder 1% and extending from the end of cylinder it past cam shaft 35, as by means of gears 3'7 and 38, so that rotation of jack shaft 36 will produce rotation of cam shaft 35.

As noted above it is desired to provide means for operating cam shafts 3t} and 35 and accessible from the end of the plate cylinder (i.c., from the side of the printing press) and outside that area of the plate cylinder surface to be covered by printing plates. In the illustrated ern= bodiment, cam shaft 3%), associated with plate 15 adjacent one end of plate cylinder 10, is provided with a worm gear meshing witha worth 41 mounted on a shaft 42,- whereby rotation of worm 41 will cause corresponding ro tation of cam shaft 30. A similar arrangement is provided for rotation of jack shaft 36 and cam shaft 35 by worm gear 45 on jack shaft 36 meshing with worm 46 on shaft 47. Since cam shaft 35 is, spaced from the end of cylinder 16, it may be desired to include some mechanical advantage or power-increasing ratio for the operating arrangement as, for example, in the gearing 37 33 between jack shaft 36 and cam shaft 35.

As illustrated in FIGS. 3 and 4, worms 41 and 46 and the shafts 42 and 47 therefor are mounted for rotation in the. end portion 11 of cylinder 10 as by brackets 50 and 51, respectively. Brackets 50 and 51 also include annular members 52 and 53, respectively, each of which has on the inner surface thereof ratchet teeth indicated at 54 and 55, respectively. Ratchet wheels and 61 are mounted on shafts 42 and 47, respectively, for rotation with worms 41 and 46 and theseratchet wheels carry pivoted spring-loaded pawls 62 and 63 for engag= ing, respectively, the ratchet teeth 54 and 55 to lock worms 41 and 46 (and, hence, cam shafts 30 and 35) in any particular angular position in which they may be placed. The outer ends of worm shafts 42 and 47 have means for receiving a wrench thereon, such as the squared portions 65 and 66 forreceivinga socket wrench 67 with which the desired rotation of cam shafts 30 and 35 is manually achieved. In the illustrated embodiment, wrench 67 has a bevelled and enlarged base socket por tion 68 of such size and configuration that, when wrench 67 is placed upon either of the squared ends- 65 or 66, the base 63 will engage the respective pawl 62 or 63 and move it out of engagement with the ratchet teeth 54 or 55 (the two positions of the pawls being illustrated in FIG. 3).

As will be apparent from the foregoing, rotation of the cam shafts 30, 35, etc., is individually'obtained, to move clamps 20 into or out of clamping engagement with plates 15, 16, etc., and from a readily accessible point at the end of plate cylinder 10; while the pawl-and-ratchet arrangements lock cam shafts 30, 35, etc., into any angular positioningas desired for register-cylinders of multicolor printingthereby locking clamps 20 into any of a variety of clamping positions for providing the desired individual clamping force on plates 15, 16, etc., despite dimensional variations which may occur among the printing plates.

There is also provided, in accordance herewith, means for adjusting the axial positioning of the plates, for precisely and minutely controlling the register of the printed image, and, preferably, such means are positioned in cylinder 10 so as to be accessible when plates 15, 16, etc., are in place on cylinder 10e.g., with the operating mechanism for the axial adjustment beingpositioned on cylinder 19 so as to be accessible in the small space between adjacent printing plates.

As indicated in the drawings, and particularly FIGS. Sand 6, such means include, in the illustrated embodiment, radially extending borings 70 in cylinder 10 and positioned axially thereof generally between axially adjacent plates. Into borings 70 are inserted rotatable cylindrical plugs 71, each of which has at the radially outer end thereof an upstanding circular bearing portion 72 protruding radially upwardly from the surface of cylinder 16) and arranged on plug 71 eccentrically with respect to the axis thereof. The diameter of bearing portion 72 and the extent of eccentricity thereof are both correlated so that portion 72 bears against the circumferential edge 73 of, for example, plate 16, whereby rotating plug 71 and eccentric portion 72 thereon will force plate 16 axially of cylinder 10.

Means, such as a square socket 74 in bearing 72, are provided for receiving an Allen wrench for rotating plug 71. and eccentric bearing 72. Also, as indicated in FIG. 6, ratchet teeth 75 are provided around the outside of plug 71 for engagement by a pawl 76 mounted in cylinder 10 to lock plug 71 in any particular angular positioning. If desired, there is provided on the top surface of plug 71 a scale indicated at 77 and visible through the space between adjacent plates whereby the extent of axial shifting of the plates in various angular positions of bearing 72 may be noted or pre-set.

It is to be understood that, for simplification of the showings in the drawings, only one axial adjustment device is shown and that the clamping mechanism for only two adjacent plates 15 and 16 has been shown. Thus, the axial displacement mechanism indicated in FIGS. and 6 is repeated for the various printing plates. Similarly, the clamping arrangements and the means for the operation thereof are also duplicated for plates in addition to 15 and 16, depending upon the total number of plates to be accommodated on plate cylinder 10. Such duplication may, as desired, be at the end of the plate cylinder opposite to that illustrated in FIG. 1 and/or in such other manner, preferably, so as to maintain circular symmetry of the weight or mass of material to be rotated with cylinder 10.

As Will be apparent from the foregoing illustrative explanation of a structure embodying and for practicing this invention, positive clamping of one axial edge of printing plates 15, 16, etc., to plate cylinder 10 is achieved by positively urging clamps 20 into clamping position by rotation of cam shafts 30 and 35, whileresilient clamping of the opposite axial edges of the plates is achieved with spring means 25. Moreover, the operation of those of the clamps 20 associated with a particularprinting plate is separately achieved by the individual operation of the several cam shafts 30, 35, etc. Similarly, the operation of all the cam shafts is achieved from operating means positioned and accessible at the end of cylinder 16, notwithstanding that one or more of such cam shaft are in the central portion of cylinder 1%) and substantially removed from either end thereof. The foregoing advantages are achieved while still permitting coaxial alignment of cam shafts 30 and 35 through the cylinder 10 and, also, coaxial alignment of the pivot axis of clamps 20 for uniform spacing and alignment of the axial edges of a plurality of printing plates along cylinder 10. There is also provided, as will be understood from the foregoing, means for axially or laterally adjusting printing plates with respect to cylinder 19, which means are provided in a manner visually and manually accessible even when the printing plates are on the cylinder and without interference with the operating means for the clamping of axial edges of the plates .to the cylinder.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to these precise methods or forms of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. In a device for clamping stereotype printing plates and the like onto the plate cylinder of a rotary printing press where at least some of said stereotype plates are spaced axially of said cylinder from either end thereof, the combination which comprises a separate set of damp ing hooks for clamping engagement with opposite axial edges of each of said plates, means for mounting said clamping hooks in said plate cylinder for clamping each individual printing plate, and individual operating means accessible at one end of said plate cylinder for separately and individually operating said clamping means for a plur ality of said sets of clamping hooks which are axially aligned along said cylinder and for clamping edges of plates axially aligned therealong.

2. In a device for clamping stereotype printing plates and the like onto the plate cylinder of a rotary printing press where at least some of said stereotype plates are spaced axially of said cylinder from either end thereof, the combination which comprises a separate set of clamping hooks for clamping engagement with opposite axial edges of each of said plates, means for pivotally mountin g said clamping hooks in said plate cylinder for arcuate swinging movement of said hooks selectively into and out of clamping engagement with said plates, rotatable cam means for swinging independently separate said sets of hooks for clamping one edge of said individual printing plates, and individual operating means accessible at one end of said plate cylinder for separately and individually operating said cam means for each of said sets of clamping hooks, some of said cam means for clamping said edges of plates spaced axially from said end of said cylinder being co axially aligned with those of said cam means for clamping said edges of plates nearer said end of said cylinder.

3. "In a device for clamping stereotype printing plates and the like onto the plate cylinder of a rotary printing press where at least some of said stereotype plates are spaced axially of said cylinder from either end thereof, the combination which comprises a separate set of clamping hooks for clamping engagement with opposite axial edges of each of said plates, means for pivotally mounting said clamping hooks in said plate cylinder for arcuate swinging movement of said hooks selectively into and out of clamping engagement with said plates, rotatable cam means for swinging independently separate said sets of hooks for clamping one edge of said individual printing plates, and individual operating means accessible at one end of said plate cylinder for separately and individually operating said cam means, said operating means including separate gear trains for rotating each of said rotatable cam means, and at least some of said rotatable 0am means being co-axially aligned in said cylinder with others of said cam means.

4. A device as recited in claim 2 in which spring means are provided for urging into clamping position those of said clamping hooks clamping said edges of said plates opposite to said edges clamped by said sets of hooks operated by said rotatable cam means.

5. A device as recited in claim 3 in which said operating means and gear train for operating those of said rotatable cam means co-axially aligned with other said cam means but spaced inwardly from said end of said cylinder include a jack shaft and gearing engaging said inwardly spaced oam means and means for rotating said jack shaft accessible from said end of said cylinder effecting rotation of said cam means notwithstanding said spacing thereof from said end of said cylinder and said co-axial alignment thereof with said other cam means nearer said end of said cylinder.

6. A device as recited in claim 5 in which said operating means and gear trains for said various cam means for operating said sets of clamping hooks include a rotatable worm meshing with a worm gear on one of said rotatable cam means adjacent said end of said cylinder for rotation of said cam means and another worm meshing with a worm gear on said jack shaft for rotating another coaxially aligned cam means spaced inwardly from said end of said cylinder.

7. A device as recited in claim 2 in which said individual operating means for operating said cam means include separate pawl-and-ratchet means associated therewith for maintaining each of said rotatable cam means in a particular angular positioning and means operating said operating means with a manually rotated wrench applied thereto and including means for disengaging said pawl from said ratchet upon application of said wrench permitting rotation of said operating means in either direction of rotation.

8. A device as recited in claim 1 in which there is also included an eccentrically rotatable bearing abutment effective on a circumferential edge of said printing plates for lateral adjustment thereof axially of said cylinder upon rotation of said eccentric bearing abutment.

9. A device as recited in claim 8 in which said eccentric bearing abutment includes pawl-and-ratchet means for maintaining said abutment in a particular angular positioning with respect to the bearing of said eccentric abutment on said circumferential edges of said plates.

References Cited in the file of this patent UNITED STATES PATENTS 449,039 Fietsch Mar. 24, 1891 1,853,208 Harrold Apr. 12, 1932 2,621,590 Faeber Dec. 16, 1952 2,832,288 Harless Apr. 29, 1958 

